Following up on yesterday's update of adding a Webmention form on IndieNews' Webmention endpoint, today I finished building out the UI for submitting to IndieNews from a browser.
Now the "Submit" link includes a form where you can paste in your post's URL, in case your website doesn't send Webmentions automatically.
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If you use this form to send the Webmention, then the response will be an HTML page instead of a JSON response. If the submission is successful, then it will actually return a 302 redirect to the IndieNews permalink of the post! This is a slight deviation from the Webmention spec, but it's fine because we don't really care if the browser is a spec-compliant Webmention client.
Also thanks to Chris Aldrich for the suggestion of using a dropdown for the target URL selection on the generic Webmention form.
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This is the form you see when you visit the Webmention endpoint, which is not specific to the language you're on.